[alsa-devel] Tascam US-122L - Corrupt USB descriptor

[Simon Wood]

Hi all,
I have been struggling for the past few days to get a Tascam US-122L (USB
sound-card/midi interface) working, despite reading numerous forum
postings I have only been able to get the midi portion working.

I note that the USB descriptor seems to be corrupt. It declares 2
interfaces, but then describes 3 separate with the same interface number
for the last 2... could it be that this is confusing the Linux USB stack?

I have attached a copy of the descriptor and an annotated 'lsusb -vv'.


>From my experience with the HID subsystem, they have a mechanism for
patching HID descriptors, is the same possible for the base USB
descriptor? Trolling through 'drivers/usb' I didn't see anything... any
suggestions?

If this is possible I can try to increase the interface count and renumber
the last one.

Cheers,
Simon.

PS. For reference the device is:
Model No: US-122L
Serial: (21)0120xxx
Other barcode: 043774021628
-------------- next part --------------
An embedded and charset-unspecified text was scrubbed...
Name: us-122l-descriptors.txt
URL: <http://mailman.alsa-project.org/pipermail/alsa-devel/attachments/20160413/89e80818/attachment.txt>